Hi @Eduardo Braga, 

Below are some information, Hope this helps:
 

Owners tab (client level only)
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The users or user groups who can access this client computer through the CommCell Console and who can run Web Console browse and restore operations on this client.

Association tab:
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Use this dialog box to add entities and roles to users and user groups. The users and user groups plus the roles plus the entity create the three-way security association.

Refer: https://documentation.commvault.com/2023e/expert/user_administration_and_security_online_help.html#add-association

Regards,

Pratik